Methanol is required for methanol-to-olefin (MTO) and many non-MTO reactor systems. Conventionally, methanol is produced at a methanol production facility that is far from the MTO or non-MTO reactor system. High quality methanol-carrying tankers have been provided to ship the methanol from the methanol production facility to the reactor system.
Methanol for non-MTO processes, e.g., MTBE and formaldehyde synthesis, must be of a high quality. A typical non-MTO process requires the methanol in its feedstock to be at least Grade A, preferably Grade AA. Because conventional methanol conversion processes require very high quality methanol, conventional methanol tankers include methanol holds that are coated with Zinc or epoxy to reduce contamination from the hold's inner surface. Additionally, large methanol-carrying tankers, e.g., Aframax class ships at 105,000 Dead Weight Tons (DWT), having tank holds greater than 3,000 m3 have implemented expensive nitrogen blanketing or “inerting” systems to prevent methanol contamination from the blanketing gas and to reduce the risk of methanol fires. Ships with less than 3,000 m3 holds, e.g., Panamax class ships at 45,000 DWT, are not required by the SOLAS (Safety of Life at Sea) U.N. resolution to have a gas blanketing system. A Nitrogen blanketing system includes very large nitrogen adsorbers or generators, which often take up a significant amount of deck space. In conventional methanol carriers, an entire deck under the bridge house can be dedicated to the nitrogen generation equipment. Additionally, the costs associated with building and maintaining a specialized methanol tanker having coated hold surfaces and an inerting system are very high. Thus, the need exists for reducing the costs associated with transporting methanol, particularly with transporting methanol to MTO reactor systems.